haddow



No. 6ll,842. Patented Oct. 4, I898. D. HUNT &. W. HADDOW.

BALL GRINDING MACHINE.

(Application filed Aug. 31, 1897.) I (No Model.) 4 SheetsShe'et I.

maceasas' THE wms PETEFIS co. wo-muwo" aas-iwCJON, n. c

P atented Oct. 4, I898. n. HUNT & w. HADDOW.

BALL GRINDING MACHINE.

(Application filed Aug. 31, 1897.)

4 8heets8heet 2. (No Model.)

THE Noam Parana co. wom-uwo. wAsmvmm n c N0. 6ll,842.. Patented Oct. 4, I898. D. HUNT &. W. HADDOW.

BALL GRINDING IIIACHIN E.

=, (Application filed Aug. 31, 1897.)

\No Model.) 4 sneaks-Sheet 3 Tu: mums PETERS co, moram-nmwumwman n. c.

No. 6ll,842. Patented Oct. 4, I898.

. D. HUNT &. W. HADDOW.

BALL GRINDING MACHINE.

(Application filed Aug. 31, 1897.) (No Model.) 4 SheetsSheet 4.

"Mum 2/ 1 5 17576 UNITED STATES PATENT FFICEQ DAVID HUNT, OF BOSTON, AND WILLIAM IIADDOVV, OF WATERTOWN, MASSACHUSETTS; SAID HADDOW ASSIGNOR TO SAID HUNT.

BALL-GRINDING MACHINE.

SPECIFICATION forming part of Letters Patent No. 611,842, dated October 4, 1898.

Application filed August 31,1897. Serial No. 650,098. (No model.)

To aZZ whom it may concern.-

Be it known that we, DAVID HUNT, of Bos ton, county of Suffolk, and WILLIAM HAD- DOW, of Watertown, county of Middlesex, State of Massachusetts, have invented an Improvement in Ball-Grinding Machines, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

This invention has for its object to construct a machine for grinding more or less spherical balls or ball-blanks to improve their sphericity, reducing them practically to true spheres.

The machine embodying this invent-ion oomprises, essentially, a rotating grinding-wheel, a rotating ball-holder, and means for moving one of said parts relatively to the other on an axis coincident with the axis of the ball which is held by said rotating ball-holder, and means for changing the position of the ball or ball-blank which is held by said ballholder in such a manner that all parts of its surface may be subjected to the action of the grinding-wheel.

The ball-holder may consist of a pair of ball-engaging pins arranged in alinement and having their engaging ends terminating a short distance apart to receive between them the ball.

The ball-holder may rotate on a horizontal axis, and it may be supported upon or by a table which is adapted to oscillate on a vertical axis coincident with the axis of the ball which is held by said ball-holder, and said table is located in front of the rotating grinding-wheel, so that as it oscillates said grinding-wheel will grind the ball on an are concentric to the axis of said oscillating table, which is also concentric to the axis of the ball being ground, the equatorial portion of the ball which is exposed between the ball-engaging pins being at such time ground.

The ball-changing device herein provided for changing the position of the ball in the ball-holder, so that its poles or underground portions of its surface may be subjected to the action of the grinding-Wheel, may consist of a pair of ball-engaging pins adapted to engage the ball that is held by said ballholder, and said ball-changing device is operated to engage said ball just as the ballholder releases it, and to then turn said ball, say, a quarter of a revolution or thereabout, and to then disengage it just as the ballholder is again operated to engage it. By giving the ball a quarter-turn its poles or underground portions of its surface, which were not previously subjected to the action of the grinding-wheel by reason of being in engagement with the ball-holder, may thu subsequently be presented.

Means are provided for automatically operating the various parts so that the ball will be engaged by the ball-holder, presented to the grinding-wheel, and oscillated. Then its position in the ball-holder will be changed and it will be again presented to the grindingwheel and oscillated, and thus its entire sur face will be acted upon by said grindingwheel.

The ball holder combined with a ballchanging device which cooperates therewith to thus handle or manipulate the ball in such manner that all parts of its surface may be exposed constitutes a special feature of this invention.

Figure 1 shows in side elevation a ball grinding machine embodying this invention; Fig. 2, a plan view of the machine shown in Fig. 1; Fig. 3, a detail showing automatic means for oscillating the table carrying the ball-holder and ball-changing device; Fig. 4, a detail showing the ball-holder and mechanism for rotating it; Fig. 5, a detail of the ball-changing device and also a part of the feeding mechanism for the balls; Fig. 6, details of the plunger which forms a cooperative part of the ball-feeding mechanism, and Fig. 7 a detail of the ball-changing device.

A represents the bed of the machine, which will be supported upon suitable standards.

A pair of guides at a are secured to the top of the bed A a suitable distance apart to provide a guideway for a slide a, which is adapted to work therein, and said slide has erected upon it a pair of uprights a M, which receive and support a shaft a upon which a grinding-wheel a is secured. This grinding-wheel may be of any suitable construc: tion, but is preferably made as a ring, held by a pair of clamping-plates, (see Fig. 1,) such construction of grinding-wheel being best suited for the present purposes, as its edge may be kept properly tapered and trued.

A driving-pulley a is also secured to the shaft a by which said shaft maybe rotated. A screw a passes freely through a smooth hole formed in a ledge a rising from the bed A, said screw entering the slide a, and the head of said screw is adapted to be brought to bear against the outer side or face of said ledge a and a bow-spring a is interposed between said slide a and ledge a the tendency of which is to thrust the slide away from the ledge until the head of the screw 0. is brought to bear against said ledge. The position of the slide,and consequently the grinding-wheel carried by it, may be thus adjusted by turning the screwa. By providing a spring-such, for instance, as the bow-spring (t -said slide a and grinding-wheel carried by it are free to yield in a direction toward the ledge. The ball to be acted upon by the grinding-wheel is fed down a vertical chute b to a horizontal delivery-tube b, which contains a plunger 6 having a cup-formed end b and said plunger normally occupies a position beneath the chute b, so as to close the entrance therefrom to the delivery-tube b, and when the parts are in such position the lowermost ball rests on said plunger. As the plunger b is withdrawn the lowermost ball which rested thereon will enter the deliverytube 1) and will drop into the cup-formed end Z) on said plunger, and as the plunger returns it will carry said ball along said tube 1) and again close the lower end of the chute b and will deliver said ball to the ball-holder. The opposite or outer end of the plunger 12* bears upon or against a cam f, which is secured to a cam-carrying shaft (Z, having its bearings in uprights or standards erected upon the bed A of the machine, and a spring I) encircles said plunger 12 which operates to continuously maintain the plunger in engagement with said cam f. The cam f operates the plunger 1) to feed the balls one at a time to the ball-holder. WVe desire it to be understood, however, that so far as this invention is concerned any form or construction of feeding device may be employed in lieu of that herein shown.

The ball-holder herein shown consists of a pair of pins 0 c, mounted horizontally in bearings 0 provided for them and arranged in alinement, and said pins 0 c are formed or provided with more or less pointed ends which terminate a short distance apart to engage the ball. The bearings c c of said ball-engaging pins 0 c are erected upon a table B, which has a circular recess formed upon its under side to receive a correspondinglyshaped projection B, erected upon the bed A of the machine, said table B being thereby free to turn or oscillate on said bed A.

In order that the ball which is held between the ball-engaging pins 0 0 may be presented to the grinding-wheel so that said wheel may grind said ball truly concentric to its axis, the table 13 is caused to turn or oscillate on a center coincident with the axis of the ball which is held by the ball-holder, and said table is thus oscillated by means that will be hereinafter described.

The ball-holder c c rotates on ahorizontal axis in a direction opposite to that of the grinding-wheel, and for the accomplishment of this result each ball-engaging pin 0 0 will have fixed to it a pinion c3 c and said pinions are engaged by toothed gears c 0, secured to a shaft 0 having its bearings in uprights 0 c and said shaft 0 has fixed to it a bevel-gear 0 which is engaged by a bevelgear 0, secured to the upper end of a vertical shaft 0 which passes down through the bed A of the machine, and has secured to its lower end a belt-pulley c", by which it may be driven. By the mechanism thus described the ball-engaging pins 0 c are rotated in unison and in the same direction, and will thereby correspondingly rotate the ball which is held by them. To engage the ball, one of said ball-engaging pins is movable toward and from the other, and, as herein shown, the pin 0 is movable axially toward and from the pin 0, and for the accomplishment of this result automatically and at predetermined times, as will be hereinafter described, a grooved pulley e is fixed to the end of the pin a, which receives projections on a yoke e, which is formed or provided at the end of a lever e, pivoted at c to a stand or upright on the bed A, and said lever extends in the opposite direction and is formed or provided at its opposite end with a curved arm efihaving a projection 6 which enters a circumferential groove formed in a cam 6, which is secured to the cam-carrying shaft d. The cam-groove in said disk is so formed as to move the lever c twice during each revolution to thereby move the pin 0' axially back and forth twice during each revolution to twice engage and disengage the ball.

The cam-carrying shaft cl is driven in any suitable way-as, for instance, it may have secured to its end a bevel-gear cl, which is engaged by a bevel-gear d secured to an oblique shaft (1 having at its lower end a worm-wheel d*, which is engaged by a worm d secured to the shaft 0 Driving mechanism for the cam-shaft (I, thus connected with the shaft 0, enables the operation of said shafts to be accurately timed, so as to rotate at a desired relation to each other.

As a means fon oscillating the table 13 on its axis, which iscoincident with the axis of the ball held by the ball-holder c c, we have herein secured to .the vertical shaft 0 a pinion n, which engages a large toothed gear at, journaled to the bed A of the machine, and said gear 01 has projecting from it a crankpin M, which enters and is adapted to work in a longitudinal slot n formed in one arm of a lever n which is loosely mounted upon said shaft 0 to turn thereon, as on a pivot, the other arm of said lever n being connected by a pin it with the table 13. As the pinion a revolves the gear a will be turned and its crankface of the ball to the action of the grindingwheel in order that it may be ground truly concentric to its axis. It is obvious,however, that manydifferent forms or constructions of devices may be provided for thus oscillating the table 13 without departing from the spirit and scope of this invention.

The table B is herein arranged to strike against the slide a at the ends of its oscillatory movement, so as to move said slide a short distance in order that the grinding-wheel borne by it may be moved away from the ball, as shown by dotted lines, Fig. 2. The ball having been engaged by the ball-holder c c and the table B having been oscillated so that the ball has been acted upon by the grinding-wheel and ground concentric to its axis along its exposed portion, it will be disengaged b'ysaid ball-holder and engaged by a ball-changing device, which operates to engage and turn it and then disengage it just as the ball-holder again operates to engage it, thereby changing its position in the balls holder, after which the table B again oscillates and the ball is again acted upon by the grinding-wheel.

As herein shown, the ball-changing device consists of a pair of ball-engaging pins m m, located one above the other in vertical alinement, the adjacent ends of which terminate a short distance apart to receive the ball between them, and said pins m m are set in the ends of a pair of levers m m which are pivoted at m to a stand on the bed A, and the opposite ends of said levers extend rearward and pass one above and the other belowa cam m fixed to the cam-carrying shaft (1, terminating, however, adjacent to said cam, so as to be acted upon by it. As the cam m separates the ends of said levers which are in engagement therewith the opposite ends of said levers will approach each other and the ballengaging pins 'm m borne by them will be brought into engagement with the ball. The parts are timed so that the ball-engaging pins m m will thus operate to engage the ball just as said ball is disengaged by the ball-holder c o. The ball-engaging pins'm m are adapted to be turned or oscillated in their bearings to thereby turn the ball, and for the accomplishment of this result said pins may have lateral projections m m which pass through slots in the ends of the levers m m and said lateral projections m m are connected by a yoke m formed on the end of a rod m which is adapted to slide back and forth in suitable bearings provided for it, the opposite end of said rod bearing upon or against a cam m which is secured to the cam-carrying shaft 66, and a spring 077, encircles said sliding rod m which tends to continuously hold said rod in engagement with said cam. As the cam m rotates the rod will be moved so as to oscillate the ball-en gaging pins m m, and thereby turnthe ball which is engaged by it. The extent of oscillation herein given to said pins is approximately ninety degrees, but they may be turned more or less. As soon as said ball has been turned the levers m m will separate to allow said pins to disengage the ball, which latter will be again engaged by the ball-holder, but its position therein will have been turned, so that as the table is again oscillated the grinding-wheel will act upon the ball and grind suchportions of its surface as were not accessible when previously subjected to the action of the grinding-wheel. It is obvious, however, that many forms or constructions of ball-engaging devices maybe employed in lieu of that herein shown, and consequently we do not desire to limit ourinvention to the particular form or construction herein shown, as we desire to broadly include within the spirit and scope of our invention any form or construction of ball-changing device which cooperates with a ball-holder to change the position of the ball therein, in order that all parts of its surface may be presented to the grinding-wheel.

We claim- 1. The combination of a rotating ball-holder, a ball-changing device, means for operating said ball-changing device to engage and disengage the ball, and means for turning said ball-changing device substantially a quarter of a revolution on an axis at right angles to the axis of rotation of' said ball-holder while in engagement with the ball to thereby change the position of the ball in said ball-holder,

substantially as described.

2. The combination of a rotating ball-holder, an oscillating support therefor turning on an axis coincident with the axis of the ball held by said ball-holder, and a ball-changing device for changing the position of the ball in said ball-holder, substantially as described.

3. Thecombination of a rotating ball-holder, and a ball-changing device oscillating on an axis coincident with the axis of the ball held by said ball-holder,substantially as described.

4. In aball-grinding machine, the combination of arotating grinding-wheel, a rotating ball-holder, means for moving one of said parts relatively to the other on an axis coincident with the axis of the ball to present the equatorial portion of the ball to said grinding-wheel, and means for turning the ball substantially a quarter of a revolution in said ball-holder to present its poles to said grinding-wheel, substantially as described.

5. In a ball-grinding machine, a rotating grinding-wheel, combined with a rotating ballholder, and a table carrying it oscillating on an axis coincident with the axis of the ball held by said ball-holder, a ball-changing device, means for operating it to engage and disengage the ball, and means for turning said ball-engaging device substantially a quarter of a revolution on an axis coincident with the axis of said table while in engagement with the ball, to thereby change the position of the ball in said ball-holder, substantially as described.

6. In a ball-grinding machine, a rotating grinding-wheel, a rotating ball-holder, and means for moving one of said parts relatively to the other on an axis coincident with the axis of the ball, combined with a ball-changing device also oscillating on an axis coincident with the axis of said ball, substantially as described.

7. In a ball-grinding machine, a rotating grinding-wheel, a rotating ball-holder, and means for moving one of said parts relatively to the other on an axis coincident with the axis of the ball held by the ball-holder, combined with a ball-changing device and means for operating it toengage the ball held by said ball-holder, and for turning it on a vertical axis and for thereafter disengaging it, substantially as described.

8. In a ball-grinding machine, the combination of a rotating grinding-wheel, a rotating ball-holder, and means for moving one of said parts relatively to the other on an axis coincident with the axis of the ball held by said ball-holder, means for operating saidballholder to engage and release the ball, a ballchanging device and means for operating it to engage the ball when released by said ballholder and for oscillating it to turn said ball, and for then releasing said ball as the ballholder again engages it, substantially as described.

9. In a ball-grinding machine, a rotating grinding-wheel, combined with a ball-holder consisting of a pair of ball-engaging pins movable one toward and from the other to engage and disengage the ball, and means for rotating both of said ball-engaging pins, and a table carrying said ball-holder, and means for oscillating it, substantially as described.

10. In a ball-grinding machine, the combination of a rotating grinding-wheel, a rotating ball-holder, and means for moving one of said parts relatively to the other on an axis coincident with the axis of the ball held by said ball-holder, and a ball-changing device consisting of a pair of ball-engaging pins movable toward and from each other to engage and disengage the ball, and means for oscillating said ball-changing device while engaging the ball, substantially as described.

11. In a ball-grinding machine, a rotating grinding-Wheel, combined with a ball-holder consisting of a pair of ball-engaging pins, automatic means for moving one toward and from the other to engage and disengage the ball, and means for rotating both of said ballengaging pins, a table carrying said ballholder and means for oscillating it, substantially as described.

12. In a ball-grinding machine, the combination of a rotating grinding-wheel, a rotating ball-holder, automatic means for moving one of said parts relatively to the other on an axis coincident with the axis of the ball being ground, an oscillating ball-changing device consisting of a pairof ball-en gagin g pins, and automatic means for moving them one toward and from the other to engage and disengage the ball, substantially as described.

13. In a ball-grinding machine, a rotating grinding-wheel, combined with a rotating ball-holder, and a table carrying it, oscillating on an axis coincident with the axis of the ball held by said ball-holder, and a ballchanging device consisting of a pair of ballengaging pins, and automatic means for moving them one toward and from the other to engage and disengage the ball, and means for oscillating said ball-engaging pins, substantially as described.

14. In a ball-grinding machine, the combination of a rotating grinding-wheel, a rotating ball-holder, and means for moving one of said parts relatively to the other on an axis coincident with the axis of the ball held by said ball-holder, a ball-changing device, and automatic means for oscillating it on an axis coincident with the axis of said ball to change the position of said ball in the ball-holder, substantially as described.

15. In a ball-grinding machine, a rotating grinding-wheel, a rotating ball-holder, an oscillating table carrying said ball-holder, and automatic means for moving said grindingwheel away from the Work at each end of the oscillatory movement of said table, substantially as described.

16. In a ball-grinding machine, a rotating grinding-wheel, a rotating ball-holder, means for oscillating one of said parts relatively to the other on an axis coincident with the axis of the ball, means for operating said ballholder to engage and release the ball, a ballchanging device, means for oscillating it on an'axis coincident with the axis of the ball,

and means for operating it to engage and re ICC IIC 

